Collaborative: Phylogeny, Character Evolution, and Diversification of Extant Ferns

点击翻译按钮获取中文摘要

9616260 Smith In a three-institution collaboration with colleagues at Utah State University and Chicago's Field Museum of Natural History, Dr. Alan Smith at University of California at Berkeley is amassing a major database of molecular and morphological characters of representatives of the 30 or so families of living ferns, in order to construct an overall phylogenetic framework for ferns. Building upon the impressive results of a 1994 symposium of fern specialists, with an international team that produced preliminary results for this effort (published in 1995), Smith and his colleagues are continuing a major DNA sequencing project for four genes, two from the chloroplast genome and two from the nucleus, that hold promise of yielding informative variation for genealogical analyses. This molecular database in turn is to be supplemented with traditional anatomical and morphological features drawn from the vegetative and reproductive parts of the same ferns analyzed for their DNA, features used standardly in their taxonomic identification and classification. A well-resolved phylogeny for ferns will facilitate future work on the patterns and sequences of character evolution that gave rise to the Cretaceous radiation and diversification of the major group of ferns, the "polypodiaceous" group, and will provide a foundation for family- and genus-level taxonomic revisionary research. Using comparative methods, researchers can explore patterns of association among characters for correlated evolutionary changes, that may help explain the success or failure (extinction) of various lineages within the ferns.